This invention relates to the field of integrated circuits; and, more particularly, to MOS transistors and their manufacture.
Integrating components such as metal oxide semiconductor field effect transistors (MOSFET) which can handle high blocking voltages into integrated circuits is problematic. High voltage transistors such as drain extended MOS transistors require large depletion regions, undesirably increasing the size and cost of the integrated circuits. Some circuits would benefit from drain extended transistors capable of both n-channel and p-channel modes of operation. Incorporating separate p-channel drain extended MOS transistors and re-channel drain extended MOS transistors in such circuits also undesirably increases the size and cost of the integrated circuits.